X0.5Sr0.5Co0.8Fe0.2O3-delta (X=Ba, La and Sm) and La0.75Sr0.25Cr0.5X0.5O3-delta (X'= Mn, Fe and Al) mixed ionic-electronic conducting perovskite-based oxides have been tested as SOFC electrode materials on La0.9Sr0.1Ga0.8Mg0.2O2.85 (LSGM) electrolytes under different atmospheres (air, oxygen, argon and dry and wet 5% H-2/Ar) and the area-specific resistances (ASR) were compared. Ba0.5Sr0.5Co0.8Fe0.2O3-delta (BSCoF) possesses the lowest ASR values in air (0.04 Omega cm(2) at 1073 K) whilst La0.75Sr0.25Cr0.5Mn0.5O3-delta (LSCrM) possesses the lowest ASR values in wet 5% H-2/Ar (0.28 Omega cm(2) at 1073 K). In addition, fuel cell tests were carried out using wet 5% H-2/Ar as fuel and air as oxidant. The maximum power density (similar to 123 mW cm(-2)) at 1073 K was reached with the electrolyte-supported system BSCoF/LSGM/LSCrM (similar to 1.5 mm electrolyte thickness). Furthermore, LSCrX' materials were used simultaneously as cathode and anode in fuel cell tests and the symmetric system LSCrM/LSGM/LSCrM (similar to 1.5 mm electrolyte thickness) reached a maximum power density of similar to 54 mW cm(-2) at 1073 K. (c) 2006 Elsevier Ltd. All rights reserved.